Assuming that you have AirPods, you can use this crazy feature. It sounds illegal, but it’s not. You can listen to conversations when you’re not in the room if you leave your iPhone there. It will send the audio to your AirPods live. Now hopefully, you’ll never be in a situation where you need to do that. But- just so you know, it’s there… Here’s a step-by-step tutorial on how to do it, you little James Bond you.